[Maximum number: 1]

Potassium iodide, KI, is used as a reagent in both inorganic and organic chemistry.

(a)

$\quad \mathrm{KI}$ is used as a source of $\mathrm{I}^{-}$ ions in organic synthesis.

One example of this is shown in the synthetic route in Fig. 1.1.

Fig. 1.1

[ 1 ]

(i)

The $\mathrm{I}^{-}$ from KI reacts with D in step 4. The mechanism is shown in Fig. 1.1. Suggest the name for this mechanism.

[ 1 ]

(a)

Both chloroalkanes and acyl chlorides react with water, but only acyl chlorides fume in moist air.

[ 1 ]

(i)

Explain why the reactivities of chloroalkanes and acyl chlorides differ.

[ 1 ]

[Maximum number: 1]

One molecule of ammonia reacts with one molecule of ethyl methanoate, $\mathrm{HCO}_{2} \mathrm{C}_{2} \mathrm{H}_{5}$ , to produce one molecule of methanamide, $\mathrm{HCONH}_{2}$ , and only one other molecule, X .

One molecule of methanamide decomposes on heating strongly to produce one molecule of ammonia and only one other molecule, Y.

What could be the identities of X and Y ?

ethanoic acid

carbon monoxide

ethanoic acid

hydrogen cyanide

ethanol

carbon monoxide

ethanol

hydrogen cyanide

(a)

Phenyl propanoate cannot be made directly from propanoic acid and phenol. Suggest the identities of the intermediate G, the reagent H and the by-product J in the following reaction scheme.

G is
H is
J is

[ 2 ]

[Maximum number: 3]

Ethanolamine and phenylamine are two organic bases that are industrially important. Ethanolamine is a useful solvent with basic properties, whilst phenylamine is an important starting material in the manufacture of dyes and pharmaceuticals. The following table lists some of their properties, together with those of propylamine.

(a)

Propylamine can be synthesised from bromoethane by the following route.

[ 3 ]

(i)

Draw the structure of the intermediate compound X in the box above.

(ii)

Suggest reagents and conditions for
step 1
step 2

[ 3 ]

(a)

Methylamine is a useful reagent in organic chemistry.

[ 2 ]

(i)

Write an equation for the reaction of ethanoyl chloride with methylamine.

[ 2 ]

[Maximum number: 1]

Part of the structure of strobilurin is shown. R and $R^{\prime}$ are inert groups.

strobilurin

Strobilurin is warmed with aqueous sulfuric acid producing compound X . Compound X is then treated with hydrogen in the presence of a nickel catalyst producing compound Y .

What could be the structure of compound Y ?

[Maximum number: 7]

Acyl chlorides are useful intermediates in organic syntheses.

(a)

(i)

State a suitable reagent for converting carboxylic acids into acyl chlorides.

(ii)

Construct an equation for the reaction between ethanoic acid, $\mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{H}$ , and the reagent you have stated in (i).

[ 2 ]

(b)

(i)

In the boxes provided draw the structures of the compounds formed when benzoyl chloride undergoes the following reactions.

(ii)

Name the functional group in
- compound A
- compound B

。

(iii)

What type of reaction is reaction II?

[ 5 ]

(c)

(i)

Suggest suitable acyl chlorides to use in the following reaction. Draw their structures in the boxes provided.

Compound E dissolves in, but does not react with, cold water.

[Maximum number: 6]

Noradrenaline is a hormone and neurotransmitter, which is released during stress to stimulate the heart and increase blood pressure.

noradrenaline

(a)

Draw the structures of the products when noradrenaline is reacted with

[ 4 ]

(i)

an excess of ethanoyl chloride, $\mathrm{CH}_{3} \mathrm{COCl}$ .

[ 4 ]

(b)

Name the new functional groups formed in the reaction in (c)(iii).

[ 2 ]

(a)

Acyl bromides, RCOBr , can be synthesised by the reaction of a carboxylic acid and $\mathrm{SOBr}_{2}$ .

This is a similar reaction to the synthesis of acyl chlorides using $\mathrm{SOCl}_{2}$ .

[ 4 ]

(i)

Give an equation for the reaction between ethanoic acid and $\mathrm{SOBr}_{2}$ .

[ 1 ]

(ii)

Suggest the relative ease of hydrolysis of acyl bromides, RCOBr , acyl chlorides, RCOCl , and alkyl chlorides, RCl.

Explain your answer. > >
easiest to hydrolyse
hardest to hydrolyse

[ 3 ]